Query the Data Delivery Network
Query the DDNThe easiest way to query any data on Splitgraph is via the "Data Delivery Network" (DDN). The DDN is a single endpoint that speaks the PostgreSQL wire protocol. Any Splitgraph user can connect to it at data.splitgraph.com:5432 and query any version of over 40,000 datasets that are hosted or proxied by Splitgraph.
For example, you can query the dycd_program_sites table in this repository, by referencing it like:
"cityofnewyork-us/dycd-program-sites-ebkm-iyma:latest"."dycd_program_sites"or in a full query, like:
SELECT
":id", -- Socrata column ID
"communitydistrict", -- Community District in which the program site is located.
"program_site_name", -- The name under which this program site is identified in DYCD systems
"borough", -- The borough for the street address of the program site.
"street_address", -- The street address of the program site.
"city", -- The city listed in the address of the program site.
"state", -- The state in which the program site is located.
"zipcode", -- The zipcode for the street address of the program site.
"latitude", -- Latitude of the program site.
"longitude", -- Longitude of the program site.
"x_coordinate", -- The NYC X-coordinate of the program site.
"y_coordinate", -- The NYC Y-coordinate of the program site.
"community_name", -- Community District in which the program site is located.
"city_council_district", -- City Council district in which the program site is located.
"census_tract_2010", -- Census tract (2010) in which the program site is located.
"nda", -- Neighborhood Development Area (if applicable) in which the program site is located. NDAs are used by DYCD to identify areas for Community Anti-Poverty Programs.
"nta", -- Neighborhood Tabulation Area in which the program site is located.
"bbl", -- The BBL (Borough, Block, and Lot) is a unique identifier for each tax lot in the City
"geocoded_column",
"ntaname", -- The neighborhood name associated with the NTA.
"totalslots", -- The number of funded slots for this program site.
"totalparticipants", -- The number of enrolled participants for this program site.
"contract", -- The DYCD contract number associated with this program site.
"portfolioid", -- The DYCD identifier used to differentiate between program sites under a contract where each program site has individual deliverables.
"age_range",
":@computed_region_efsh_h5xi",
":@computed_region_sbqj_enih",
":@computed_region_92fq_4b7q",
":@computed_region_yeji_bk3q",
":@computed_region_f5dn_yrer",
"bin", -- The BIN (Building Identification Number) is a unique identifier for each building in the City
"date", -- Fiscal Year during which the program site was operating.
"program_area", -- DYCD unit monitoring this program site
"program_type", -- The program model (within the broader Program Area) under which this program site operates
"service_category", -- Type of services provided at this site for this contract, used for identification on DiscoverDYCD. Each Program Type has one or more associated Service Categories.
"provider" -- The community-based organization associated with this contract and workscope.
FROM
"cityofnewyork-us/dycd-program-sites-ebkm-iyma:latest"."dycd_program_sites"
LIMIT 100;Connecting to the DDN is easy. All you need is an existing SQL client that can connect to Postgres. As long as you have a SQL client ready, you'll be able to query cityofnewyork-us/dycd-program-sites-ebkm-iyma with SQL in under 60 seconds.
Query Your Local Engine
bash -c "$(curl -sL https://github.com/splitgraph/splitgraph/releases/latest/download/install.sh)"Read the installation docs.
Splitgraph Cloud is built around Splitgraph Core (GitHub), which includes a local Splitgraph Engine packaged as a Docker image. Splitgraph Cloud is basically a scaled-up version of that local Engine. When you query the Data Delivery Network or the REST API, we mount the relevant datasets in an Engine on our servers and execute your query on it.
It's possible to run this engine locally. You'll need a Mac, Windows or Linux system to install sgr, and a Docker installation to run the engine. You don't need to know how to actually use Docker; sgrcan manage the image, container and volume for you.
There are a few ways to ingest data into the local engine.
For external repositories, the Splitgraph Engine can "mount" upstream data sources by using sgr mount. This feature is built around Postgres Foreign Data Wrappers (FDW). You can write custom "mount handlers" for any upstream data source. For an example, we blogged about making a custom mount handler for HackerNews stories.
For hosted datasets (like this repository), where the author has pushed Splitgraph Images to the repository, you can "clone" and/or "checkout" the data using sgr cloneand sgr checkout.
Cloning Data
Because cityofnewyork-us/dycd-program-sites-ebkm-iyma:latest is a Splitgraph Image, you can clone the data from Spltgraph Cloud to your local engine, where you can query it like any other Postgres database, using any of your existing tools.
First, install Splitgraph if you haven't already.
Clone the metadata with sgr clone
This will be quick, and does not download the actual data.
sgr clone cityofnewyork-us/dycd-program-sites-ebkm-iymaCheckout the data
Once you've cloned the data, you need to "checkout" the tag that you want. For example, to checkout the latest tag:
sgr checkout cityofnewyork-us/dycd-program-sites-ebkm-iyma:latestThis will download all the objects for the latest tag of cityofnewyork-us/dycd-program-sites-ebkm-iyma and load them into the Splitgraph Engine. Depending on your connection speed and the size of the data, you will need to wait for the checkout to complete. Once it's complete, you will be able to query the data like you would any other Postgres database.
Alternatively, use "layered checkout" to avoid downloading all the data
The data in cityofnewyork-us/dycd-program-sites-ebkm-iyma:latest is 0 bytes. If this is too big to download all at once, or perhaps you only need to query a subset of it, you can use a layered checkout.:
sgr checkout --layered cityofnewyork-us/dycd-program-sites-ebkm-iyma:latestThis will not download all the data, but it will create a schema comprised of foreign tables, that you can query as you would any other data. Splitgraph will lazily download the required objects as you query the data. In some cases, this might be faster or more efficient than a regular checkout.
Read the layered querying documentation to learn about when and why you might want to use layered queries.
Query the data with your existing tools
Once you've loaded the data into your local Splitgraph Engine, you can query it with any of your existing tools. As far as they're concerned, cityofnewyork-us/dycd-program-sites-ebkm-iyma is just another Postgres schema.